A comparative study of the effect of intravenous mannitol injection during surgery on the rate of delayed transplant performance in kidney transplant recipients in Hashminejad Hospital

Determining the effect of intraoperative intravenous mannitol injection on the rate of delayed graft function in kidney transplant recipients.

This research is a Phase 2-3 randomized controlled clinical trial with a parallel-group, triple-blind design, conducted on 120 kidney transplant recipients. Patients will be randomly allocated to either the intervention or control group using the RAND function in Microsoft Excel.

This triple-blind, block-randomized trial at Hasheminejad Hospital will compare intraoperative 20% mannitol versus 0.9% saline in kidney transplant patients. After multidisciplinary approval, patients will be randomized to either group. Identical administration protocols will be used, with patients, anesthesiologists, and outcome assessors blinded to assignment.

Inclusion Criteria: First-time kidney transplant recipient. Age 18–70 years. Surgery performed within the study period. Approval by a multidisciplinary team (Psychiatry, Nephrology, Surgery). Transplant benefits outweigh the risks. Able to tolerate surgery and immunosuppressive drugs. Exclusion Criteria: Undergone renal autotransplantation. Known hypersensitivity to mannitol. Occurrence of any adverse reaction or complication that cannot be controlled during the study.

The intervention group will receive 20% mannitol solution at a dose of 0.5 mL per kilogram of body weight (concentration: 0.5 mL = 1 gram). The control group will receive 0.9% sodium chloride solution at the same dose of 0.5 mL per kilogram. The maximum total dose of the study solution is limited to 50 mL. A 10 mL bolus of the assigned solution will be administered just before graft reperfusion, and the remaining volume will be infused continuously until the end of the surgery.

Delayed Graft Function

Randomization Method: Block randomization will be used. Patients will be allocated to either the intervention (mannitol) or control (placebo) group using the block randomization method. This approach ensures that the number of patients in the two groups remains approximately balanced throughout the study. Unit of Randomization: Individual (patient). Randomization Tool: Microsoft Excel with the RAND function will be used. Random Sequence Generation: To perform block randomization with a block size of 4 in Excel, all possible balanced permutations of two patients allocated to group "A" (e.g., mannitol) and two to group "B" (placebo) are first listed in a column. Next to each permutation, a random number is generated using the RAND function for each row. By sorting the entire list based on the column of random numbers (in ascending or descending order), the final sequence of blocks is determined randomly. This randomized sequence of consecutive 4‑patient blocks then forms the master allocation list. Allocation Concealment: To maintain concealment, the allocation list will be stored and implemented using serially numbered, opaque, sealed envelopes or a secure electronic system.

This study is designed as a triple-blinded trial to prevent any bias in the intervention and outcome assessment. Patients will be unaware of their assignment to the intervention or control group, as the injected solutions (20% mannitol and 0.9% normal saline) will be identical in appearance, volume, and administration method, prepared in identical, unlabeled containers. The anesthesiologist administering the solution will also be blinded to its nature (active drug or placebo), since the preparation and coding of the solutions will be performed by an independent staff member not involved in the trial. Furthermore, the outcome assessor (who records and adjudicates endpoint data such as dialysis requirement, serum creatinine levels, and biopsy results) will remain blinded to the group allocation codes. The allocation sequence will be kept in serially numbered, opaque, sealed envelopes or a secure electronic system and will be disclosed only in the event of a medical emergency.